AccessRunner ADSL-USB Modem Device Set Data Sheet
4.1.5
Enumeration
The enumeration process consists of the following steps:
1. Get device descriptor. The host requests and reads the device descriptor to determine maximum packet size.
2. Set address. The host sends the function address in a data packet using function endpoint 0. Device firmware interprets
this data.
3. Get device descriptor. The host requests and reads the device descriptor to determine such information as device class,
USB Specification compliance level, maximum packet size for endpoint 0, vendor id, product id. Etc.
4. Get configuration descriptor. The host requests and reads the device configuration descriptor to determine such
information as the number of interfaces and endpoints; endpoint transfer type, packet size, and direction; power source
;maximum power; etc. When the host requests the configuration descriptor, all related interface and endpoint descriptors
are returned.
5. Set configuration. The host assigns a configuration value to the device to establish the current configuration.
4.1.6
Endpoint Pairs
Data transfers with the host are made to/from endpoint pairs on the USB module. The five function endpoint pairs are listed in
Table 4-5.
Table 4-5. Endpoint Pairs
Endpoint Pair
Max. Packet Size
Max. Packet Size
USB Data Transfer Types
Function Endpoint 0
Function Endpoint 1
Function Endpoint 2
Function Endpoint 3
Function Endpoint 4
64 bytes
64 bytes
64 bytes
64 bytes
64 bytes
64 bytes
64 bytes
64 bytes
Control
Bulk
Bulk
Bulk
Bulk
64 bytes
64 bytes
4.1.7
Language ID Table
See Language ID data in Table 4-6.
Table 4-6. Language ID Table
Offset
Field
Size
Value
Default
(Hex.)
Description
0
1
2
bLength
bDescriptorType
1
1
2
Number
Constant
Number
04
03
Size of this descriptor in bytes.
INTERFACE Descriptor Type.
0409
4.1.8
Manufacturer String Table
See Manufacturer String data in Table 4-7.
Table 4-7. Manufacturer String Table
Offset
Field
Size
Value
Default
(Hex.)
Description
0
1
2
bLength
bDescriptorType
1
1
2
Number
04
03
00
'-'
Size of this descriptor in bytes.
Constant
INTERFACE Descriptor Type.
Manufacturer string, in unicode
4-6
Conexant
100427B